Events should be posted in the correct section, and in date order. An event should NEVER be listed in more than one section (i.e. Ongoing/Continuous events should not be listed in Scheduled Training). When events begin the same day, events of a longer length should be listed first. New postings of events with the same date(s) as other events should be added after events already in the list. If a provider offers the same event at several locations simultaneously, the listing should have a single (ONE) entry in the list with the date(s) and ALL locations for the event. Please use three-letter month abbreviations (i.e. Sep, NOT Sept. or September), use two digit dates (i.e. Jan 01 NOT Jan 1), and use date ranges rather than listing every date during an event(i.e. Jan 02-05, NOT Jan 02, 03, 04, 05).<br>

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Windows Prefetch files, introduced in [[Windows|Windows XP]], are designed to speed up the application startup process. Prefetch files contain the name of the executable, a Unicode list of DLLs used by that executable, a count of how many times the executable has been run, and a timestamp indicating the last time the program was run. Although Prefetch is present in Windows 2003, by default it is only enabled for boot prefetching. The feature is also found in [[Windows Vista]], where it has been augmented with [[SuperFetch]], [[ReadyBoot]], and [[ReadyBoost]].

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<i>Some events may be <u>limited</u> to <b>Law Enforcement Only</b> or to a specific audience. Such restrictions should be noted when known.</i>

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This is a BY DATE listing of upcoming events relevant to [[digital forensics]]. It is not an all inclusive list, but includes most well-known activities. Some events may duplicate events on the generic [[conferences]] page, but entries in this list have specific dates and locations for the upcoming event.

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Up to 128 Prefetch files are stored in the <tt>%SystemRoot%\Prefetch</tt> directory [http://blogs.msdn.com/ryanmy/archive/2005/05/25/421882.aspx]. Each file in that directory should contain the name of the application (up to eight (?) characters), a dash, and then an eight character hash of the location from which that application was run, and a <tt>.pf</tt> extension. The filenames should be all uppercase except for the extension. The format of hashes is not known. A sample filename for [[md5deep]] would look like: <tt>MD5DEEP.EXE-4F89AB0C.pf</tt>. If an application is run from two different locations on the drive (i.e. the user runs <tt>C:\md5deep.exe</tt> and then <tt>C:\Apps\Hashing\md5deep.exe</tt>), there will be two different prefetch files in the Prefetch folder.

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This listing is divided into four sections (described as follows):<br>

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<ol><li><b><u>Calls For Papers</u></b> - Calls for papers for either Journals or for Conferences, relevant to Digital Forensics (Name, Closing Date, URL)</li><br>

<li><b><u>On-Going / Continuous Training</u></b> - Training opportunities that are either always available online/distance learning format (start anytime) or that are offered the same time every month (Name, date-if applicable, URL)</li><br>

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<li><b><u>[[Scheduled Training Courses]]</u></b> - Training Classes/Courses that are scheduled for specific dates/locations. This would include online (or distance learning format) courses which begin on specific dates, instead of the "start anytime" courses listed in the previous section. (Provider, URL) (''note: this has been moved to its own page.'')<br></li></ol>

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The Conference and Training List is provided by the American Academy of Forensic Sciences (AAFS) Digital and Multimedia Sciences Section Listserv.

Each Prefetch file has a signature in the first 8 bytes of the file. Windows XP and Windows Vista will generate Prefetch files with the signature \x11\x00\x00\x00\x53\x43\x43\x41 (0x41434353 0x00000011). Windows 7 Prefetch file's signature is \x17\x00\x00\x00\x53\x43\x43\x41 (0x41434353 0x00000017). The [http://en.wikipedia.org/wiki/ASCII ASCII] representation of these bytes will display "....SCCA".

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Requests for additions, deletions or corrections to this list may be sent by email to David Baker <i>(bakerd AT mitre.org)</i>.

Both the [[NTFS]] timestamps for a Prefetch file and the timestamp embedded in each Prefetch file contain valuable information. The timestamp embedded within the Prefetch file is a 64-bit (QWORD) [http://msdn2.microsoft.com/en-us/library/ms724284.aspx FILETIME] object The creation date of the file indicates the first time the application was executed. Both the modification date of the file and the embedded timestamp indicate the last time the application was executed.

* [http://www.kdnuggets.com/meetings/ Meetings and Conferences in Data Mining and Discovery]

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A timestamp of when the application was last ran is embedded into the Prefetch file. The offset to the "Last Run Time" is located at offset 0x78 from the beginning of the file on [[Windows]] XP. The offset for Windows Vista and Windows 7 is at 0x80.

In each Prefetch file, the size of the header is stored and can be found at offset 0x54 on Windows XP, Windows Vista, and Windows 7. The header size for Windows XP is 0x98 (152) and 0xf0 (240) on Windows Vista and Windows 7.

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The Prefetch file will embed the application's name into the header at offset 0x10.

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==== Run Count ====

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The run count, or number of times the application has been run, is a 4-byte (DWORD) value located at offset 0x90 from the beginning of the file on [[Windows]] XP. On Windows Vista and Windows 7, the run time can be found at 0x98.

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==== Volume ====

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Volume related information, volume path and volume serial number, are embedded into the Prefetch file. The precise offset for this information varies for each application ran. In the header at offset 0x6c, the location of the volume path is stored. The location is a 4-bytes (DWORD) value. The offset 0x6c is consistent for Windows XP and Windows 7.

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At the location given from 0ffst 0x6c, a 4 byte value is stored which is the number of bytes from current offset (location from offset 0x6c) to the beginning of the volume path. The location from offset 0x6c, for ease, will be called the "volume path offset." The volume path is embedded as a NULL-terminating string.

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The length of the volume path is a 4-byte value is located at volume path offset + 0x4.

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The volume [http://en.wikipedia.org/wiki/Volume_serial_number serial number] is a 4-byte value that identifies a media storage. A serial number does not have a consistent offset within a Prefetch between Windows operating systems. The 4-byte value can be found eight (8) bytes from the creation time location.

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== Issues ==

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==== End of File ====

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Prefetch files generated by the Windows operating system does not have any signature or sequences of bytes to indicate when the end of the Prefetch file has been reached.

* [http://msdn.microsoft.com/msdnmag/issues/01/12/XPKernel/default.aspx More detail from Microsoft]

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* [http://www.tzworks.net/prototype_page.php?proto_id=1 Windows Prefetch parser] Free tool that can be run on Windows, Linux or Mac OS-X.

Revision as of 22:52, 2 July 2011

Please help to improve this article by expanding it.
Further information might be found on the discussion page.

Windows Prefetch files, introduced in Windows XP, are designed to speed up the application startup process. Prefetch files contain the name of the executable, a Unicode list of DLLs used by that executable, a count of how many times the executable has been run, and a timestamp indicating the last time the program was run. Although Prefetch is present in Windows 2003, by default it is only enabled for boot prefetching. The feature is also found in Windows Vista, where it has been augmented with SuperFetch, ReadyBoot, and ReadyBoost.

Up to 128 Prefetch files are stored in the %SystemRoot%\Prefetch directory [1]. Each file in that directory should contain the name of the application (up to eight (?) characters), a dash, and then an eight character hash of the location from which that application was run, and a .pf extension. The filenames should be all uppercase except for the extension. The format of hashes is not known. A sample filename for md5deep would look like: MD5DEEP.EXE-4F89AB0C.pf. If an application is run from two different locations on the drive (i.e. the user runs C:\md5deep.exe and then C:\Apps\Hashing\md5deep.exe), there will be two different prefetch files in the Prefetch folder.

Contents

Signature

Each Prefetch file has a signature in the first 8 bytes of the file. Windows XP and Windows Vista will generate Prefetch files with the signature \x11\x00\x00\x00\x53\x43\x43\x41 (0x41434353 0x00000011). Windows 7 Prefetch file's signature is \x17\x00\x00\x00\x53\x43\x43\x41 (0x41434353 0x00000017). The ASCII representation of these bytes will display "....SCCA".

Timestamps

Both the NTFS timestamps for a Prefetch file and the timestamp embedded in each Prefetch file contain valuable information. The timestamp embedded within the Prefetch file is a 64-bit (QWORD) FILETIME object The creation date of the file indicates the first time the application was executed. Both the modification date of the file and the embedded timestamp indicate the last time the application was executed.

Creation Time

The creation time does not have a static offset on any Windows platform. The location of the creation time can be found using the offset 0x8 + length of Volume path offset.

Last Run Time

A timestamp of when the application was last ran is embedded into the Prefetch file. The offset to the "Last Run Time" is located at offset 0x78 from the beginning of the file on Windows XP. The offset for Windows Vista and Windows 7 is at 0x80.

MetaData

Header

In each Prefetch file, the size of the header is stored and can be found at offset 0x54 on Windows XP, Windows Vista, and Windows 7. The header size for Windows XP is 0x98 (152) and 0xf0 (240) on Windows Vista and Windows 7.

The Prefetch file will embed the application's name into the header at offset 0x10.

Run Count

The run count, or number of times the application has been run, is a 4-byte (DWORD) value located at offset 0x90 from the beginning of the file on Windows XP. On Windows Vista and Windows 7, the run time can be found at 0x98.

Volume

Volume related information, volume path and volume serial number, are embedded into the Prefetch file. The precise offset for this information varies for each application ran. In the header at offset 0x6c, the location of the volume path is stored. The location is a 4-bytes (DWORD) value. The offset 0x6c is consistent for Windows XP and Windows 7.

At the location given from 0ffst 0x6c, a 4 byte value is stored which is the number of bytes from current offset (location from offset 0x6c) to the beginning of the volume path. The location from offset 0x6c, for ease, will be called the "volume path offset." The volume path is embedded as a NULL-terminating string.

The length of the volume path is a 4-byte value is located at volume path offset + 0x4.

The volume serial number is a 4-byte value that identifies a media storage. A serial number does not have a consistent offset within a Prefetch between Windows operating systems. The 4-byte value can be found eight (8) bytes from the creation time location.

Issues

End of File

Prefetch files generated by the Windows operating system does not have any signature or sequences of bytes to indicate when the end of the Prefetch file has been reached.